Can someone explain the difference between backticks and system when
evaluated in these if statements:
sub getDate {
print "start date\n";
if ( system("/bin/date") ) {
print "can't get date\n";
exit(2);
}
print "finish date\n";
}
Returns the following:
start date
Thu... (5 Replies)
Hi, I'm trying to do something like this: range= `expr `date '+%m'` - 1` and it does not work. How can I tell it to evaluate an expression within another expression evaluation? I was at first worried that `date '+%m'` would return a string but apparently expr does the math okay normally, so the... (3 Replies)
Hi,
I would like to change some lines in my mysql-dump, because there a syntax problems with some version of mysql.
I 'd like to change
USE ´someDatabase´;
to
USE someDatabase;
(without backticks) using the sed command in the shell
Thanks & best regards
Bernd (5 Replies)
I'm always concerned I might be abusing backticks within my scripts. A current script I'm writing has this for example:
stripscriptname=`echo $scriptname | sed 's/\(.*\)\..*/\1/'`
stripsearch=`echo $searchpattern | tr -d ' ,/'`
Both of these variables are set inside the script (in fact,... (2 Replies)
Hey all. Just a fast question, what is the technical difference between using back ticks and using xargs to perform a command?
Here's an example
Find /mydir -name *.conf |xargs rm
Vs
Rm 'find /mydir -name *.conf'
Is there a performance hit? I know they do the same thing but which is... (1 Reply)
Hi everyone. This is a bit of a perl/linux mixed question. I am trying to redirect STDOUT of chsh by using the following line of perl code.
system ("chsh -s /sbin/nologin $testing 1>/dev/null");
This should redirect STDOUT to /dev/null but it won't do that for some odd reason. Any ideas or... (6 Replies)
Input file:
'data_1'
'data_10'
'data1311'
'235data_13'
Desired output:
data_1
data_10
data1311
235data_13
Can I know how to remove back tick"'" in a file?
Many thanks for advice. (3 Replies)
I have been testing a new script and cannot figure out why my `cat spath` will not execute on the remote machine?
sudo ssh -p 22344 -o "PasswordAuthentication no" -o "HostbasedAuthentication yes" -l testuser 192.168.1.6 "find `cat spath` -depth"
cat: spath: No such file or directory
but... (0 Replies)
I'm trying to make a dialog window that prints the output of grep that takes the output of find. Unfortunately my nested backticks don't work.
Here is the dialog window:
dialog --stdout --title "test" --backtitle "test" --msgbox "Test:\n `grep -l "${tablica}" `find $string``" 16 60I think I... (2 Replies)
Discussion started by: Starting_Leaf
2 Replies
LEARN ABOUT HPUX
read
read(1) General Commands Manual read(1)NAME
read - read a line from standard input
SYNOPSIS
var ...
DESCRIPTION
reads a single line from standard input. The line is split into fields as when processed by the shell (refer to shells in the first field
is assigned to the first variable var, the second field to the second variable var, and so forth. If there are more fields than there are
specified var operands, the remaining fields and their intervening separators are assigned to the last var. If there are more vars than
fields, the remaining vars are set to empty strings.
The setting of variables specified by the var operands affect the current shell execution environment.
Standard input to can be redirected from a text file.
Since affects the current shell execution environment, it is usually provided as a normal shell special (built-in) command. Thus, if it is
called in a subshell or separate utility execution environment similar to the following, it does not affect the shell variables in the
caller's environment:
Options
recognizes the following options:
Do not treat a backslash character in any special way.
Consider each backslash to be part of the input line.
Opperands
recognizes the following operands:
var The name of an existing or nonexisting shell variable.
EXTERNAL INFLUENCES
Environment Variables
determines the internal field separators used to delimit fields.
RETURN VALUE
exits with one of the following values:
0 Successful completion.
>0 End-of-file was detected or an error occurred.
EXAMPLES
Print a file with the first field of each line moved to the end of the line.
while read -r xx yy
do
printf "%s %s
" "$yy" "$xx"
done < input_file
SEE ALSO csh(1), ksh(1), sh(1), sh-posix(1).
STANDARDS CONFORMANCE read(1)